Abrading machine



A ViiiLLEU NHER ABRADING MACHINE Jan. 3, 1933.

Filed Oct. 15 1927 Fig.4.

INVENTOR.,

E Q gm WV T m% H13 HTTORNE opposed to one another to form a Patented Jan. 3, 1933 UNITED STATES PATENT oFFrcr-i ALBERT 'VUILLEUIIEB, C1 BRISTOL, CONNECTICUT, ASSIGNOB TO THE NEW DE- PABTUBCB IANUFACTURING COIPANY, OF BRISTOL, CONNECTICUT, 'A CORZPOBA TION OF CONNECTICUT Lemme 11mm Application filed October 18,1887. Serial No. 228,005.

This invention relates to abrading machines and comprises all the features and aspects of novelty herein disclosed in connec tion with a method and apparatus for feed ng 5 balls through a. centerless grinding machine having ved wheels.

An ob ect of the invention is to provide an improved mechanism for intermittently feeding balls between rooved wheels of a centerless inding mac ine in such manner that all t e grooves are used to the same extent and kept of the roper depth and form by the action of the ba ls themselves. a

To these ends and to improve generally u on methods and devices of this general c aracter, the invention also consists in the various matters hereinafter described and claimed.

In the drawing Figure 1 is a top view of the feed mechanism with the wheels omitted.

Figure 2 is a side elevation with some parts in section, the wheels being omitted.

Fi re .3 is a. small scale front and showing the relation of the wheels to important elements of the feed mechanism.

Figure 5 is a pers ective view of a portion of the feedv plate and adjacent parts.

Fi re 6 is a diagrammatic side view of a portion of the feed plate and grinding wheel.

The apparatus is intended more especially for use with a ball grinding machine of the centerless type having wheels peripherally n ing throat. In Figures 3 and 4, the bro en lines indicate the wheels, one wheel 10 being a grinding wheel which rotates at high 5 eed in a downward direction at the work an the other wheel 12 being a, slow or regulating wheel which moves upwardly at the work, the axis of the wheel 12 being tilted upwardly at the front in order to cause the work to rotate on constantly changing axes while supported J by the upper inclined edge of a blade or work support 14. In the ordinary centerless grinder having smooth wheels, the tilting of the slow wheel is intended to produce a continuous feeding movement of the work along the elevation work support but in the present instance the igure 4 is a diagrammatic plan view.

wheels are grooved and the work is positively fed intermittently when the grinding wheel 10 and the regulating wheel 12 are separated to let the work pass from roove to oove. In the illustrated construction, the w eel 12 is intermittently retracted by a supporting slide 16 which also carries the work support.

Each wheel has, a series of eripheral ball grooves 18 opposed to similar hall grooves on the other w eel and the grooves are spaced a art a distance less than ball diameter so t at, at any one time, the balls cannot occupy adjacent grooves but can occupy alternate grooves. The balls first occupy one set of alternate grooves and then are advanced to the intermediate coves so that the rooves and intervening IlbS wear down equa ly and preserve the depth and form of the grooves. n order to keep the machine loaded with balls, at new ball is inserted when one of the ground balls is ejected but inasmuch as the loaded balls cannot occupy adjacent rooves, a new ball is inserted onl upon the a ternate advances of the loaded ba ls. A peculiar kind of feed mechanism is accordingly utilized: It comprises a toothed plate or comb 20 having teeth 22 spaced a art twice as far as the ball grooves. The eed plate 20 is reciprocated intermittently in a whenever the regulating whe is retracted to let the loaded balls pass the ribs from groove to groove. p

The feed plate 20 first has a half stroke forward equlvalent to the distance between adjacent ball grooves, or half the distance between the feed plate notches, then another half stroke forward, and then a full stroke backwards while being lifted over the loaded balls. As indicated diagrammatically in Figure 6, the loaded balls may occupy the first, third, fifth, etc. grooves in the wheels and the feed plate is shown in its retracted position ready to recelve a new ball A.

When the feed plate is advanced half a-.

peculiar way e the new ball A is advanced to the-position B where it is still outside the first groove. On the second half of the forward stroke, the new ball is moved into the position 0 in the first groove while the remaining loaded balls are advanced to the third, fifth, seventh, etc. grooves. On the full return stroke, the feed plate is retracted to its ori inal position as will appear. The cooperating ball grooves are progressively shallower up to the last few rooves which are alike in depth to ive the fialls a finish but the difference in epth is very slight, just enough to compensate for the larger size of the unground balls.

The feed plate or comb 20 is vertically movable in a recess 24 in a horizontal feed slide 26, the feed plate being guided vertically by pins 28 pro ecting from the feed slide 26 into slots 30 in the feed plate. Gibs 32 at the ends of the feed plate hold it in the recess 24 of the slide 26 and help to guide it. The horizontal feed slide has guiding heads or flanges 34 and 36 at the ends, the front head 34 being slidably retained by gibs 38 and 40 attached to projecting lugs on an upright standard 42 and the rear head 36 being slldably retained by gibs 44 and 46 on an upright standard 48 bolted to the rear of a casting 50. The feed slide 26 is pivotally connected by a link 52 to a triangular lever 54 pivoted at 56 to the standard 42. The triangular lever 54 is pivotally connected at 58 to a fork 60 on an arm 62 pinned to the upper end of a plunger 64 which is guided lon itudinally in a casing 66 having a fork 68 oosely hung on a cam shaft 70 which is actuated in timed relation to the mechanism (not shown) which intermittently reciprocates the slide 16 which supports the regulating wheel and work support of the centerless grinder. The plunger 64 carries a cam roller 72 which is pressed by a spring 74 against a cam '26 fixed to the cam shaft between the arms of the fork 68. The cam has,

first, a portion 7 8 which imparts a half forward stroke to the feed slide 26 when the regulating wheel is retracted; second, a dwell which holds the slide and feed plate in position while grinding the balls in one set of alternate grooves; third, a rise 82 which imparts the second half forward stroke to the "feed slide; fourth, a dwell 84 which holds the feed slide and feed plate in ad- -vanced position while grinding the balls in the succeeding grooves; fifth, a drop 86 which retracts the feed slide and feed plate a full stroke to its original position while the balls remain in grinding position; sixth, a dwell 88 during which a new ball enters the feed plate and grinding of the others continues. If desired, a latch 89 with bevelled end may be spring pressed into a notch 90 in the guiding head 34 to help locate the feed slide accurately in its middle position.

When the feed plate ,20 is retracted, the inclines presented by the back sdes of the teeth 22 will lift the feed plate over the balls but the following positive lifting device is also preferably employed. Attached to the feed plate 20 are lifting plates 92 with lifting pins 94 which'pro ect into the ath of lateral cam extensions 96 on bell cran levers 98, each pivoted to an adjustable supporting bar 100 and each normally pressed by acoil spring 102 against a stop pin 104. As the feed plate is moved forwardly to the end of its second half stroke, the lifting pins 94 are carried forwardly under the cams 96, which swing upwardl to let them by, and upon the retraction of t e feed plate, the lifting ins ride up over the cams and so lift the eed plate, letting it down a ain when the cams have been traversedoil springs 106, at-

tached to the lifting plates 92 and to theadjacent guide pins 28, insure the downward movement of the feed plate.

To admit the balls intermittently to the notch between the first two teeth 22 of the feed plate, the balls are led downwardly in a stream through a feed pipe 110 into an inclined passage or opening 112 in a feed block 114 fastened to the castmg 50. The lowermost ball is temporarily retained in the feed block by a thin shutter 116 which is fastened to the feed plate and overlies the opening in the feed block until the feed plate is fully retracted. Then the ball drops into the notch and upon the bevelled 11 per edge of the blade or work support 14. support 14 is cut out a little as at 117 toreceive the lower portion of the shutter which is extended a little below the feed late in order to retain the balls in the feed lock passage when the feed plate is lifted over the loaded balls. Also, since the pressure of the stream of balls in the feed pipe might otherwise force the entering ball laterally across. the work support, a retaining plate 1I8is attached to the side of the work support op osite the feed block. This will retain the all until the shutter 116 closes the feed opening in its forward movement. The finished balls are ejectedone by one by the feed plate from the work supporting blade onto an inclined run-V way 120 in the standard 48 from which they go to a chute 122. The work sup rt or blade 14 is clamped in vertically a justed position as it wears by clamping bolts 124. The upper corner of the work support or blade 14 adjacent to the wheel 10 is scalloped as indicated in Figure 4 to fit close up to the wheel and its grooves.

Summarizing a cycle, the regulating wheel being retracted, a new ball is fed forward by the feed plate one step and simultaneously the already loaded balls in alternate grooves are all advanced to the next grooves. The regulating wheel is then returned and the balls are partly ground. The regulating wheel is again retracted and the feed plate advances another step to carry the new ball between the wheels into the first groove and simultaneously all the loaded balls are again advanced to the next grooves. The regulatne edge of the work ing wheel advances again and the balls are ground some more. The feed 'plate is retracted over the loaded balls while grinding continues and when the regulating wheel is again retracted, the cycle is repeated.

I claim:

1. In a grinding machine having opposed wheels, one wheel being a grinding wheel rotatable at high speed and the other being a regulating wheel rotating at slow speed, at least one of the wheels having a series of ball grooves, a feed plate having ball engaging members spaced twice as far apart as the ball grooves, and means for advancing the plate two groove spaces forwardly intermittently and retractin it two spaces backwardly at one stroke; su stantially as-described.

2. In a grinding machine having opposed wheels with cooperating ball grooves, a feed plate having ball engaging teeth, a slide for advancing the plate to advance the balls from groove to groove, and means for moving the .feed plate transversely with respect to the slide to clear the balls when the slide is retracted; substantially as described.

3. In a grinding machinehaving opposed wheels with cooperating ball engaging surfaces comprising grooves on at least one wheel, a feed plate having ball engaging teeth, one side of each tooth having'a cam surface, a slide for advancing the plate to advance the balls from groove to groove, a movable connection between the slide and the feed plate, and means for retracting the slide to cause the cam surfaces to lift the feed plate over the balls; substantially as described.

4. In a rinding machine having opposed wheels wit cooperating ball grooves, a slide, means for reciprocatin the slide, and a toothed feed plate mova ly mounted on the slide to enable the teeth to clear the balls in one direction; substantially as described.

5. In a grinding machine having opposed wheels with cooperating ball grooves, a feed plate having ball engaging teeth spaced twice as far apart as the ball grooves, and means for intermittently advancing and retracting the plate in timed relation to the separation of the wheels; substantially as described.

6. In a grinding machine having opposed wheels with cooperating ball grooves, a toothed feed plate, means for reciprocatin the feed plate, a feed block having a bal opening, and a shutter plate carried by the feed plate and reciprocating across the opening; substantially as described.

7. In a grinding machine having opposed wheels with cooperating ball grooves, a feed plate having ball engaging teeth, means for reciprocating the feed plate to advance the balls from groove to groove, and lifting cams for lifting the feed plate over the balls; substantially as described.

8. In a grinding machine having opposed wheels with cooperating ball grooves, a feed plate having ball engaging teeth, a feed slide, means for slidably mounting the feed plate on the feed slide, means for reciprocating the feed slide, and cams operable on one stroke of the feed slide to lift the feed teethover the balls; substantially as described.

9. In'a grinding machine having grooved wheels, a reciprocating toothed member movable forwardly by two intermittent feed steps to carry a ball into the first groove and to advance the loaded balls from groove to groove at each of said steps, and means for returning the toothed member in one movement to receive a new ball; substantially as described. p

10. In a ball grinding machine having opposed wheels with co-operating ball engaging surfaces comprising grooves on at least one wheel, a work support extendin between the wheels to support the balls or travel from groove to groove, a feed plate having ball engaging teeth spaced twice as far apart as the ball grooves, and means for advancing the feed plate two groove spaces forwardly in two stages and retracting it backwardly in one stage; substantially as described.

11. In a ball grinding machine having opposed wheels with co-operating ball engaging surfaces com rising grooves on at least one wheel, a worfi blade extendin between the wheels to support the balls or travel from groove to groove, a feed plate above the work blade and having ball engaging teeth projecting downwardly towards the work blade, and means for advancing the feed plate forwardly in two stages and retracting it backwardly in one; substantially as described.

12. In a ball grinding machine having opposed wheels with co-oper'ating ball engaging surfaces comprising grooves on at least one wheel, a work blade extendin between the wheels to support the balls %or travel from roove to groove, a feed plate above the work lade and having ball engaging teeth projecting downwardly towards the work blade, means for advancing the feed plate forwardly in two stages and retracting it backwardly in one, and means for elevating said feed plate to clear the balls in its backward movement; substantially as described.

13. In a ball inding machine having opposed wheels with co-operating ball grooves, a work-blade extending between the wheels to support the balls for travel from groove to groove, a feed plate having ball engaging teeth projecting downwardly towards the work blade, a slide for advancing the feed plate to advance the balls from groove to groove, and means for raising and lowering the feed plate on the slide; substantially as described.

In testimony whereof I hereunto aflix my signature.

ALBERT VUILLEUMIER. 

